Gas-check for projectiles.



No. 628,!06. Patented July 4, I899.

H. s. mxlm & m1. DAWSON. I

fiAS CK PROJECTILES,

cation e Aug.24,1898.) (No Model.) 2 Sheets-Sheet l (No Model.)

No. 628,)6. Patented July 4, 1899. H. s. MAXIM & A. T. DAWSON. GAS CHECKFOR PROJECTILES.

(Application filed Aug. 24, 189B.)

2 Sheets-Sheet 2 iniren Shires Mir-int @rric ENG-LAND, ASSZGNORS TO8A....IE PLACE.

THE VICKERS, SONS Ch MAXIM, Ll'llilTED, OF

it PRGJECTFLES.

S?ECIFZOATIGN forming part of Letters lifetent No. 628,106, dated July4-, 1 899. Application filed August 24, 1898. Serial No. 689377 (Nomodel.)

To all whom it may cancer/tr Be it known that we, HIRAM STEVENS :aiAXIM,a citizen of the United States, Chevalier of the Legion of Honor andcivil and mechanical en gi neer,and ARTHUR Tnnvon DAW- SON, a subject ofthe Queen of Great Britain, late of the Royal Navy, both residingat 2SVictoriastreet, London, England, have invented certain new and usefulImprovements in Gas Checks forProiec-tiles, of which The following is aspecification.

It has heretofore been usual to provide projectiles with means forpreventing or diniinthe bore of a n when heavy charges are used therein.in 5 inc cases ithns been customary to equip the projectile with a ordisk so arranged in combination with plastic ring or gas-check that atthe moment of the discharge of gun the gas-check u "ll be subjected toeater pres e per sr uare inch of its area. than that existing in the gunat the rear of the projectile.

The object of our present invention is to produce a eck or ring of thischaracter cspeeiellydes for the projectiles of heavy guns, which, whilesuflicientlyplastic to adapt itself to the bore of the gun, will havegreater stability and will he capable of resisting a greater shearingstress than the rings formed of wax, plumbztgo, and asbestos heretoforeused.

In order that our improvement may he clearly understood and readilycarried into effect, we shall describe the same with reference to theaccompanying four figures of drawings, which are sectional views showingthe improved gas-check in its preferred and modified forms andillustrating the manner of applying it. to different forms or"projectile;

Figure 1 illustrates the whole of the rear] portion of a projectileprovided with bur improved gas-check; but tlrereinaining figures showonly so much of the rear end of the pro jectile, the annular base-piece,and the pies tic ring as is necessary for a proper cornpre hensiou ofthe inztnnerin which our invention is or may be utilized or applied Inallthe-figures, A is the projectile, and a flange D which lies directlyin cont isning the erosive eiiecis of the explo ve upon the boss at thebase thereof. B is the annw 5o lar hase-pieceor collar, G the plasticring or gas-check, and Dthe driving-hand.

Referring more particularly to Fig. l, the periphery of the boss a isscrew-threaded to receive the corresponding screw-threaded portion Z) ofthe annular piece or collar B, the direction of the screw-threads beingopposii i that of the riding of the gun. The sai ,nnular piece or collarB is dished at h to in. part elasticity to said collar and toforiu theforwardly-projecting peripheral porti l r the plastic ring C. This ringis co of copper wires 0, embedded in ashes -i wax and pluinhego and t "dand coated orcovered w enieter of the projectile is di at it", so thatthe flange b of the ennui ,r p B, although not greater in diameter thant drivingbsnd D, can act upon the plastic i C. in some cases, h wever,the diameter of the said annular piece 13 may be large snow to engagewith the rifling'of the gun. ih plastic ring C is formed with a shoulderc to lit the corresponding shoulder formed by diminishing the diameterof the projectile at ct,

such shoulder effectually preventing the plastic ring from shiftingforwardly when acted upon bythe flange of the annular piece 13. Weprefer to constructthe driving-band as shown at (1, so as to prevent theentrance of the projectile too far into the gun in cases Where the boreis too loose-for example, when it has been enlarged by erosion.

The plastic ring is in the above-described construction unprovided withthe metallic coating or covering; but in Figs. 2, 3, and 4 such coatingor covering is shown on the ring. In Fig. 2 it consists of numerousconvolutions of thin wire 0 wound around the circumference of the ring.In Figs. 3 and +1- it consists of a casing 0 inclosing the saidring onits exposed surfaces. In these examples the metallic coating or coveringmay be opplied to. the ring by electrodeposition, or at thin casing ofsheet metal of thcpropcr shape and dimensions may he made and be appliedto the said ringin an y appropriate manner The plastic ring is in Fig. 4made wider than that shown in the previous figures; so as to overlap therear portion of the band D. In other respects the construction of theparts shown in Figs. 2, 3, and 4 is similar to that illustrated inFig. 1. p

In the foregoing constructions the pressure of gas acting behind theannular piece B has to crush or deform the latter before the plasticring 0 can be compressed suificiently to force it radially outwardagainst the bore of the gun.

Having now described our invention, What We claim is- 1. The gas-checkfor projectiles herein de-' scribed, consisting of a ring composed ofwire coils or rings embedded in a mass of plastic material compacted andmolded to the proper form under pressure.

2. The gas-check for projectiles herein described consisting of aplastic ring composed of wire coils or rings embedded in a compactedmass of asbestos saturated with a mixture of wax and plumbago.

3. The gas-check for projectiles herein described consisting of a ringcomposed of wire coils or rings embedded in a mass of plastic material,compacted and molded to the proper form under pressure and coated orcovered with a metal such as copper.

In testimony whereof we have hereunto set our hands, in presence of twosubscribing witnesses, this 29th day of- July, 1898,

HIRAM STEVENS MAXIM. ARTHUR TREVOR DAWSON.

Witnesses:

JOHN G. SHIELDS, WALTER W. THORPE.

